What is a PV fuse?
Fuses are designed to break a circuit when a certain current level is exceeded for a certain period of time. Thus, they perform a protective function for cables and equipment. At the same time, the risk of personal injury is reduced. PV fuses are also called overcurrent protection devices because they protect cables and equipment from so-called overcurrents when more current than expected flows through them. There are two types of overcurrents that can occur. One is overload currents caused by too many electrical loads and overload currents caused by short circuits. For example, an overload current occurs when a single load in a circuit is overloaded. In its basic function, a PV fuse can be understood as a resistor capable of completely interrupting the flow of electrical current. This occurs when the current flow exceeds a predefined threshold and can be mechanical or electrical.
How does a fuse work?
Fuses are differentiated according to three criteria, namely rated current, design and tripping characteristics. The rated current of the fuse is always at least equal to the operating current rating of all loads connected to the mains. If a fuse with a lower rated current is used, the fuse will trip even if no overcurrent occurs. The circuit will not be fully functional. Current ratings range from low milliamps to several hundred amps, depending on the fuse application. Depending on the type of fuse, it will trip differently and can be reactivated depending on the design.
Difference between fuses and multiple fuses
Fuses are irreversibly destroyed when they blow and must be replaced in any case. The service life of a switchable fuse is specified by the respective manufacturer in the switching mode. They can run into the five-digit range. Do not repair or bypass the fuse after it has tripped, but replace it with a new one, otherwise there is a safety risk.